On "Inside Politics," King played a clip of former White House communications director Anthony Scaramucci telling MSNBC's "Morning Joe" that a fact-checking campaign of his old boss wasn't the right way to go about countering him.

"If you want to beat the president, exposing his lies or explaining them to people, that's probably not going to beat the president," Scaramucci said. "There's symbolism here. You can call out the lying, but it's literally teflon in a frying pan."

King said Scaramucci's remarks were "stunning."

"He does not dispute the president's lying. The president think's you're stupid," King said, pointing and speaking directly to the camera. "The president thinks people are stupid."

Time magazine correspondent Molly Ball said Trump thinks people "don't care," and she added many of Trump's supporters likely voted for him in 2016 knowing he was often not truthful.

Trump has faced criticism for recent remarks about trying to pass a middle-class tax cut and referencing "Middle Easterners" as part of a migrant caravan making their way through Mexico, without offering evidence.

CNN anchors John Berman and Alisyn Camerota framed Trump's remarks about taxes as suggesting he would get the tax cut passed before the elections even though Congress is out of session. However, Trump said on Monday any such cut would have to be passed after the midterms.